Torbjörn Oskar Caspersson (15 October 1910 – 7 December 1997) was a Swedish cytologist and geneticist.
He was born in Motala and attended the University of Stockholm, where he studied medicine and biophysics.
Caspersson made several key contributions to biology.
In 1977 he retired as head of the medical cell research and genetics department at the Karolinska Institute in Stockholm In 1979 Caspersson was awarded the Balzan Prize for Biology "For his fundamental studies on protein metabolism and nucleic acids, culminating in a method for identifying specific bands on individual chromosomes by ultraviolet microscopy, thereby creating a new tool for the study of evolution" (motivation of the Balzan General Prize Committee).
He was a member of both the American Academy of Arts and Sciences and the American Philosophical Society.